In recent years, there is known medical treatment devices having a treatment energy application structure for applying energy to a body tissue to perform a treatment (sealing or anastomosis) on a body tissue
In a traditional method treatment energy application structure comprises a flexible substrate, a heat transfer plate, and an adhesive sheet.
The flexible substrate is a portion that serves as a sheet heater. The flexible substrate has, on one surface thereof, an electric resistance pattern for generating heat by power supply, and a lead wire connection portion which is configured to be electrically connected to the electric resistance pattern and to which a lead wire is connected.
The heat transfer plate is formed of a conducting material such as copper. The heat transfer plate faces one surface (the electric resistance pattern) of the flexible substrate and is configured to contact a body tissue to transfer a heat generated from the electric resistance pattern to the body tissue (to apply heat energy to the body tissue).
The adhesive sheet has good thermal conductivity and electrical insulation properties. The adhesive sheet is interposed between the flexible substrate and the heat transfer plate and allows them to adhere to each other.
Here, the adhesive sheet comprises a first area in which the adhesive sheet covers the entirety of the heat transfer plate when viewed from the thickness direction of the adhesive sheet and a second area in which the adhesive sheet protrudes from the heat transfer plate and covers a part of the lead wire connection portion. That is, the adhesive sheet has a function of thermally connecting the heat transfer plate and the electric resistance pattern to each other and preventing short-circuiting of the heat transfer plate and the electric resistance pattern by the use of the first area and has a function of preventing short-circuiting of the heat transfer plate and the lead wire connection portion by the second area.